title: An updated meta-analysis on the association of MDM2 SNP309 polymorphism with colorectal cancer risk.
abstract: BACKGROUND
  The mouse double minute 2 (MDM2) gene encodes a phosphoprotein that interacts with P53 and negatively regulates its activity. The SNP309 polymorphism (T-G) in the promoter of MDM2 gene has been reported to be associated with enhanced MDM2 expression and tumor development. Studies investigating the association between MDM2 SNP309 polymorphism and colorectal cancer (CRC) risk reported conflicting results. We performed a meta-analysis of all available studies to explore the association of this polymorphism with CRC risk.
  
  
  METHODS
  All studies published up to July 2013 on the association between MDM2 SNP309 polymorphism and CRC risk were identified by searching electronic databases PubMed, EMBASE, and Chinese Biomedical Literature database (CBM) databases. The association between the MDM2 SNP309 polymorphism and CRC risk was assessed by odds ratios (ORs) together with their 95% confidence intervals (CIs).
  
  
  RESULTS
  A total of 14 case-control studies including 4460 CRC cases and 4828 controls were identified. We did not find a significant association between the MDM2 SNP309 polymorphism and CRC risk in all genetic models in overall population. However, in subgroup analysis by ethnicity, significant associations were found in Asians (TG vs. TT: OR = 1.197, 95% CI = 1.055-1.358, P=0.005; GG+TG vs. TT: OR = 1.246, 95% CI = 1.106-1.404, P=0.000) and Africans. When stratified by HWE in controls, significantly increased risk was also found among the studies consistent with HWE (TG vs. TT: OR = 1.166, 95% CI = 1.037-1.311, P= 0.010). In subgroup analysis according to p53 mutation status, and gender, no any significant association was detected.
  
  
  CONCLUSIONS
  The present meta-analysis suggests that the MDM2 is a candidate gene for CRC susceptibility. The MDM2 SNP309 polymorphism may be a risk factor for CRC in Asians.
authors.affiliation: Department of Clinical Laboratory, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Qin
authors.forename: Qiliu
authors.initials: Q
authors.lastname: Peng
authors.forename: Weizhong
authors.initials: W
authors.lastname: Tang
authors.forename: Xianjun
authors.initials: X
authors.lastname: Lao
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Chen
authors.forename: Hao
authors.initials: H
authors.lastname: Lai
authors.forename: Yan
authors.initials: Y
authors.lastname: Deng
authors.forename: Cuiju
authors.initials: C
authors.lastname: Mo
authors.forename: Jingzhe
authors.initials: J
authors.lastname: Sui
authors.forename: Junrong
authors.initials: J
authors.lastname: Wu
authors.forename: Limin
authors.initials: L
authors.lastname: Zhai
authors.forename: Shi
authors.initials: S
authors.lastname: Yang
authors.forename: Shan
authors.initials: S
authors.lastname: Li
authors.forename: Jinmin
authors.initials: J
authors.lastname: Zhao
mesh_terms: D044466:Asian People / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000453:epidemiology* / Q000235:genetics*; D056726:Genetic Association Studies; D006801:Humans; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D051736:Proto-Oncogene Proteins c-mdm2 / Q000235:genetics*; D012044:Regression Analysis; D012307:Risk Factors
chemical_list: C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2